On Thu, Feb 20, 2020 at 04:41:27PM -0800, ira.weiny@xxxxxxxxx wrote:
> From: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> xfs_inode_supports_dax() should reflect if the inode can support DAX not
> that it is enabled for DAX.
>
> Change the use of xfs_inode_supports_dax() to reflect only if the inode
> and underlying storage support dax.
>
> Add a new function xfs_inode_enable_dax() which reflects if the inode
Heavily into bikeshedding here, but "enable" sounds like a verb, but
this function doesn't actually turn dax on for a file, it merely decides
if we /should/ turn it on.
xfs_inode_wants_dax() ?
--D
> should be enabled for DAX.
>
> Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>
>
> ---
> Changes from v3:
> Update functions and names to be more clear
> Update commit message
> Merge with
> 'fs/xfs: Clean up DAX support check'
> don't allow IS_DAX() on a directory
> use STATIC macro for static
> make xfs_inode_supports_dax() static
> ---
> fs/xfs/xfs_iops.c | 25 +++++++++++++++++++------
> 1 file changed, 19 insertions(+), 6 deletions(-)
>
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 81f2f93caec0..ff711efc5247 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -1237,19 +1237,18 @@ static const struct inode_operations xfs_inline_symlink_inode_operations = {
> };
>
> /* Figure out if this file actually supports DAX. */
> -static bool
> +STATIC bool
> xfs_inode_supports_dax(
> struct xfs_inode *ip)
> {
> struct xfs_mount *mp = ip->i_mount;
>
> /* Only supported on non-reflinked files. */
> - if (!S_ISREG(VFS_I(ip)->i_mode) || xfs_is_reflink_inode(ip))
> + if (xfs_is_reflink_inode(ip))
> return false;
>
> - /* DAX mount option or DAX iflag must be set. */
> - if (!(mp->m_flags & XFS_MOUNT_DAX) &&
> - !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
> + /* Only supported on regular files. */
> + if (!S_ISREG(VFS_I(ip)->i_mode))
> return false;
>
> /* Block size must match page size */
> @@ -1260,6 +1259,20 @@ xfs_inode_supports_dax(
> return xfs_inode_buftarg(ip)->bt_daxdev != NULL;
> }
>
> +STATIC bool
> +xfs_inode_enable_dax(
> + struct xfs_inode *ip)
> +{
> + if (!xfs_inode_supports_dax(ip))
> + return false;
> +
> + if (ip->i_d.di_flags2 & XFS_DIFLAG2_DAX)
> + return true;
> + if (ip->i_mount->m_flags & XFS_MOUNT_DAX)
> + return true;
> + return false;
> +}
> +
> STATIC void
> xfs_diflags_to_iflags(
> struct inode *inode,
> @@ -1278,7 +1291,7 @@ xfs_diflags_to_iflags(
> inode->i_flags |= S_SYNC;
> if (flags & XFS_DIFLAG_NOATIME)
> inode->i_flags |= S_NOATIME;
> - if (xfs_inode_supports_dax(ip))
> + if (xfs_inode_enable_dax(ip))
> inode->i_flags |= S_DAX;
> }
>
> --
> 2.21.0
>
